Internal-combustion engine



Nov. 20 1923.

F. D. SHEPHERD INTERNAL COMBUSTION ENGINE Filed Jan. 19. 1920 2 Sheets-Sheet 1 r r I Nov. 20 1923. 3,4743% "I F. D. SHEPHERD INTERNAL COMBUSTION ENGINE Filed Jan. 19. 1920 2 Sheets-Sheet 2 J nun 1 fox Patented Nov. 22, 1923.

earner orricia FRANK n. sn nrn nnn, or ermit, MICHIGAN.

INTERNAL-COMBUSTION ENGINE.

Application filed January 19, 1920. Serial No. 352,359.

To all whom it may concern:

Be it known that I, FRANK l). SHEPHERD, a citizen of the United States, residing at Detroit, State of Michigan, have invented certain new and useful Improvements in Internal-Combustion Engines, of which the following is a specification.

The present invention relates to internal combustion engines, and more particularly to the valve mechanism thereof, the object being to provide a simple,'effective and practical structure in which the valve will have a free floating movement without the danger of oifse't seating and side wear, thus insuring long life and proper gas-tight seating and avoiding the necessity of repeated regrindings.

The invention is applicable to various well known types of internal combustion engines, both of the L and T-head form, and is also peculiarly adaptable for use in high compression engines. It may be employed with detachable and integral heads and engines of the air or water-cooled type. a

In the accompanying drawings, several embodiments of the invention are disclosed, wherein Figure l is a vertical longitudinal sectional view through a portion of an internal combustion engine, illustrating the preferred embodiment of the invention,

Figure 2 is a plan view with portions broken away,

Figure 3 is a detail sectional view illustrating the initial formation of the engine head and the valve stem guide bushings, and indicating th manner in which the two are assembled, b

Figure 4 is a longitudinal sectional view through a slightly modified form of construction, p

Figure 5 is a horizontal sectional view of a twin container for a single cylinder.

Figure 6 is a plan view of the same,

Figure 7 is a detail sectional view-through the stem cap of Figure 1, illustrating the heat insulator removed therefrom,

Figure 8 is a detail sectional view of a slightly modified form of cap. I I Figure 9 is a plan view of a slightly different embodiment of stem, V

Figure 10 is a view partly in elevation and partly in longitudinal section of said stem, a

Figures 11, 12, 13 and 14 ar plan views of 'difierent embodiments of the invention,

Figure 15 is a side elevation of the structure illustrated in Figure 14, showing an air cooled container unit. 7

Similar reference numerals designate corresponding parts in all the figures of the drawings.

In the embodiment disclosed in Figures 1, 2, 3 and 7, the cylinder of the engine is designated 16 and contains the usual reciprocatory piston 17. The combustion or explosive chamber is designated 18, and has the usual offset portion 19 provided with intake and exhaust ports, one of which is illustrated at 20. Surrounding the inner end of the port is a valve seat 21, and controlling the port is a movable poppet valve 22 that cooperates with the seat 21 in a manner readily understood. The opening movement of the valve is accomplished by suitable cam mechanism, one of the cams being shown at 23 and operating on a lifter rod mechanism, designated generally by the reference numeral 2d. The valve stem 24* is slidable in a guide bushing 25, and its inner end is provided with a head 26 engaged in a recess 27 formed in the seating side of th valve 22, the stem being free from said valve, and the recess 27 being of greater diameter than the head 26 so as to pern'iit relative lateral play between these two bearing elements, The portion of the stem 24%, between the guide 25 and the head 26 is preferably reduced in diameter, as shown at 28, this alfording clearance and permit- 99 ting said portion to enlarge under the action of heat without its sticking in the guide 25.

The head of the cylinder shown in Figure 1 is designated 29, and is removable in a manner readily understood. It is preferably provided with the usual water chamber 30, and has mounted thereon a gas-tight container 31. This gas-tight containermay be of a variety of formations, but as illus- 100 trated in Figure 2, consists of an elongated housing 32, within which are a plurality of cylinder elements 33 spacedfrom the walls of thehousing, and providing a cooling chamber surrounding each of the elements 33, This chamber has communication with the chamber 30 of the head 29 through suitableports 34, but means are also provided for supplying a cooling medium from an independent source to the chamber. To thisend, the outer housing wall 32 is provided at one end with an intake port 35 and the opposite wall at the other end has an outlet end 36. The lower port is normally closed by a plug 37 when the device is used to th cooling system.

The engine head 29 is provided with a series of openings 38 axially aligned with the respective cylinder elements 33, and with the valve 22. In these openings are fixed bushings 39 preferably of relatively thin metal, so that they will receive proper cooling action from the chamber 30. In this embodiment of the invention, the bushings have at their inner ends integral flanges 40 that are-substantially dovetail in form and are interlocked in dovetail recesses 41 formed in the inner side of the engine head. As shown in Figure 3 the flanges initially are set at an inclination to the bushing walls, so that their outer edges will pass freely into the recesses 41, and the arrangement is such that when the bushings are pressed to place, the flanges will lie flush with the inner face of the engine head, and will be properly interlocked, as illustrated in Figure 1.

The valve 22 in this embodiment of the invention is provided with an integral stem 42 that extends across the combustion chamber and is slidable in the bushing 39, said stem projecting into the adjacent container. The portion between the bushing and the valve 22 is reduced in diameter as shown at 43, thereby aflording clearance, as will be readily, understood. The clearance moreover provides a sharp shoulder at its outer end that will cut away any formation of carbon in the guideway. The portion of the valve in the bushing is provided with a longitudinal bore 44 that opens through the outer end of said stem, and the stem furthermore has lateral ports 45 opening from.

the said bore 44 through the surface of the stem within the bushing. Hard heat-resisting lubricant such as graphite and the like, is located in the bore and the ports, and is designated 46, this material thus serving to effectivelylubricate the sliding surfaces, as will be obvious. The outer end of the bore is preferably closed by a plug 47 of suitable material, this plug having a head 48 that fits into an enlarged undercut portion of the bore. The plug may be cast into the said bore or the stem upset after its insertion.

Located on the outer end of the stem 42 is a cap 49, the inner side of said cap being recessed to receive the stem and a sheet of heat-insulating material, such as asbestos out. The cap 52 will cooperate with a flat surface of the container, and a packing gasket 54 can be readily interposed between the two. This is also true of the seating surfaces between the container and the en gine head, wherein a. similar packing gasket 55 may be utilized. A further and important feature of'the invention is the location of the securing bolts56 for the gas-tight container on the inner sides of the walls thereof. To this end, these walls are provided with internal ribs 57 having bores to receive the said bolts. This is particularly advantageous where the cylinder block is narrow, in that the bolts and the engaging means therefor can be within the plane of the housing walls. The particular combination disclosed is also peculiarly eflicacious in preserving the temper of the springs 51v It will be noted that each gas-tight container is effectively cooled, and that the valve stems project suflic-iently far intosaid gas-tight containers to provide relatively sufiicient air spaces between the engine head and the springengaging head. Said spring engaging head is also spaced a relatively sufficient distance from the container walls, and this is also true of the inner end of the spring- 51. As a consequence any heat that may be transmitted by convection from the engine head will have to pass through a consider- 3.

able amount of air in circulation, and very little heat will reach the spring. The walls of the container are cooled by radiation and this in turn keeps the internal conditions of the container at a low temperature Furthermore the heat transmitted by conduction through the valve stem will be stopped to a very materialdegree by the insulator interposed between the stem and cap 49. so'that the spring will under all conditions be maintained at a relatively low temperature. This will be clear as indicated by the arrows illustrated. Thus it will be evident that the air space around the valve stem head and against which the springv bears is relatively large and the constant movement of said head will create a circulation of airfabout the same. Additionally as the air is heated, it will rise in the central portion of the gastight container and the walls of said container beingcool, the air will be cooled and moved downwardly around the spring, thus eifectively cooling the same.

The embodiment disclosed in Figure 4 has many of the features'already described and corresponding advantages. The engine cylinder is designated 16 and contains a movable valve 22 cooperating with a seat 21 The cam actuated stem for said valve is designated 24 and is integral with the valve. In this embodiment the upper stem is disconnected from the valve and is desig nated generally by the reference numeral 42, being provided with a reduced clearance or portion 48 in the combustion chamber. The bushing 39 has its flange 4&0 at the outer end, and seated in an undercut recess 41 The stem has a bore filled with lubricant 46 that also fills ports 47 communicating with the bore of the bushing 39 The bore of the valve stem is closed, as in the former case, by a plug 48 The head of the stem 42 is designated 49* and in this instance is integral with the stem. It is located in a gas-tight container 31 the joints of which are closed'by, gaskets 54* and and in which is placed a tapered spring 51 that bears upon the head 49 and thus acts to close the valve. It will be noted that the securing bolts 56 of this gas-tight container are located within the plane of the outer walls. In this form of construction, the gas-tight container is aircooled, and various formations thereof may be employed. Thus, as illustrated in Figure 11, a series of these separate containers 31 may be formed with ribs thereon with central bolt openings 82 therein. In Figure 12 is shown a series of cylinder elements in an integral unit, the same being designated 31, and having bolt receiving openings 32, which it will be observed are located within the plane of the side walls of the container.

In Figure 13 the cylinder elements of the gas-tight container are designated 31, and are spaced apart by integral webs 82 having alternately opposite bolt-receiving openings 33 Figure 14 illustrates a structure in which the gas-tight container elements 81 are also connected by integral webs 32", the width of which is equal to'the outer diameter of the elements 31. In this instance, sets of bolt openings 33 are provided, the same however, being inset within the plane of the sides of the container. An individual cap for eachgastight container element or a continuous cap, as shown at 34 may be employed, secured by the bolts 35 that are passed through the openings 33.

Figure 15 illustrates a side elevation of the structure shown in Figure 14-, and it will be noted that the side walls are open so as to expose the webs and permit the tree circulation of air therearound.

For each cylinder of an engine the gastight container may have twin cylinder elements as shown at 81 in Figure 5, these elements being separated and inclosed in a suitable housing 32 with internal side ribs 83 and external end ribs 34- to receive the fastening bolts.

In Figure 6 there is illustrated a modified form of cap, in which the outer ends of the gas-tight cylinder elements are closed by screw plugs, one of which is shown at 35. The outer valve stems may also be of different formations. Thus, it will be noted that in Figure 1 the clearance portion 43 is tapered toward the valve. In Figure 10 there is illustrated a valve 42 having its inner clearance portion 43 tapered toward the body of the stem or away from the valve, as will be evident. The cap 49 may also be modified. Thus in Figure 8, a cap 49 is shown having a central seat 50 for the stem, and having an integral plug 51 that will enter the bore of the stem, as will be obvious.

From the foregoing, it is thought that the construction, operation and many advantages of the herein described invention will be apparent to those skilled in the art, without further description, and it will be understood that various changes in the size, shape, proportion and minor details of construction within the scope of the claim, may be resorted to without departing from the spirit or sacrificing any of the advantages of the invention.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is

The combination with an internal combustion engine having a plurality of ports, of valves controlling the ports and having stems projecting through a wall of the engine, a body block mounted on the engine and having a plurality of cylindrical chambers therein, side by side and of the same diameter, said chambers opening through both sides of the body and having their inner ends closed by gas-tight joints, the valve stems extending into the chambers, closures for the outer ends of the chambers, and valve actuating means in the various chambers operating on the stems.

In testimony whereof, I aflix my signature.

FRANK D. SHEPHERD. 

